Signaling system



March 22, 1938. Q OFFEL 2,111,646

SIGNALING SYSTEM Filed June 1, 1936 lMPULSE RE 6/ 5 71:7?

MARGINAL POLARIZED imm ATTOR EV Patented 22, 1938 UiTE STATES PATENT OFFICE SIGNALING SYSTEM Application June 1, 1936, Serial No. 82,914

8 Claims.

This invention relates to signaling systems and particularly to systems in which signals are transmitted by impulses of current and it is the object of this invention to insure accurate and reliable 5 signaling.

In systems employing current impulses for the transmission of signals, satisfactory operation of the signal receiving means requires that the impulses be of a certain minimum duration; and, to enable adjustment of the impulse device at the sending end of the signaling circuit, it is necessary that means be provided for measuring the length of the impulses. One such impulse measuring device, disclosed in Patent 1,976,503 granted to F. Kuchas, October 9, 1934, consists of an impulse receiving relay for responding to the impulse, a set of three auxiliary relays controlled by the impulse receiving relay, and a condensertimed test relay controlled by the auxiliary re lays. This invention is an improved impulse measuring device which consists of animpulse receiving relay for responding to impulses and a condenser-timed test relay controlled directly by the impulse receiving relay, no auxiliary relays or equivalent control apparatus being required.

The invention will be further described by considering specific embodiments shown schematically in the drawing which forms a part of this 30 specification. The invention is, however, not limited to these particular arrangements, but is in general applicable to all impulse signaling systems. Referring to the drawing:

Fig. 1 represents a system in which all of the signal impulses are of like character; and

Fig. 2 represents a system in which the signaling impulses vary in direction and magnitude.

The signaling system of Fig. 1 comprises im-,

of its lower Winding in series with resistor I2,

and relay i3 is biased by the e-nergization of its upper winding in series with resistor M; so that these relays hold their armatures in the positions 5 shown when there is no current through their operating windings; The operating (upper) winding of relay I l is connected in series with line H! for energization in responseto each impulse created by the operation of the signal sending relay 9. The operating (lower) winding of relay I3 is connected in series with condenser l5, any current through this winding being due either to the charging or discharging of condenser l5. Normally condenser is charged, the charging circuit being traced through the back contacts of relays II and I3. Upon operation of relay 1 I, by an impulse through its operating Winding, this charging circuit is opened; and condenser l5 discharges through resistor Hi, the current through the lower winding of relay l3 causing the operation of this relay for an interval of time which depends upon the capacity of condenser Hi and the value of resistor I6. By a proper choice of these elements, test relay 13 will remain operated for a desired interval of time, which interval is the length of time that impulse relay H is operated by an impulse of minimum allowable length. If the current impulse which energizes the operating winding of relay II is equal to or longer than the minimum allowable impulse, relay l3 will release at the same time or before relay II releases; but; if the current impulse which energizes the operating winding of relay II is less than the minimum allowable impulse, relay it releases while relay I3 is operated thereby closing a circuit through the back contact of relay H and front contact of relay I 3 to operate an alarm l9.

In case the signal impulses consist of interruptions of the current over line H), the armature of relay [3 will be connected to a front contact of relay H; and, in this case, reoperation of relay 5 prior to the release of relay 13 will close the alarm circuit to indicate too short an impulse.

Application of the invention to an automatic or semi-automatic telephone system in which the current impulses vary in polarity and amplitude is illustrated in Fig. 2. Reference may be had to Patent 1,840,132 granted to T. H. Roberts, January 5, i932, and to the aforementioned Kuchas patent for a complete description of a register sender arranged to transmit such current impulses. The impulses transmitted over line are of three kinds, one is a negative impulse of a certain amplitude; another is a positive impulse of the same certain. amplitude; and the third is a negative impulse of considerably larger amplitude. The impulse measuring apparatus con sists of three impulse receiving relays 2|, 22 and 23 connected in series to the signal line 20, the test relays 24, and 26 and auxiliary relays and 3|. An impulse register of any suitable type for registering the impulses received by relays 2 l 22 and 23 forms a part of the test mechanism. Relay 2| is operatively responsive to both the weaker and the stronger negative impulses, relay 22 is operatively responsive to the positive impulses, and relay 23 is operatively responsive only to the stronger negative impulses. Each of these impulses must be as long or longer than the minimum interval which is required for operation of the impulse register which is fully illustrated and described in Patent No. 1,464,084 granted to A. E. Lundell et a1., August 7, 1923. Each of the test relays 24, 25 and 26 is similar to relay |3 of Fig. 1 and is operated for a definite interval of time, when the associated impulse receiving relay 0perates, by the discharge of the condenser which is in series with its operating winding. Thus, upon the operation of impulse relay 2 condenser 21 discharges through the lower winding of test relay 24 thereby operating and holding relay 24 for the interval of time that relay 2| is operated by a weaker negative impulse of minimum allowable duration. Upon operation of impulse relay 22, condenser 28 discharges through the lower winding of test relay 25, thereby operating and holding relay 25 for the interval of time that relay 22 is operated by a positive impulse of minimum allowable duration. And upon operation of impulse relay 23, condenser 29 discharges through the lower winding of test relay 26, thereby operating and holding relay 2B for the interval of time that relay 23 is operated by a stronger negative impulse of minimum allowable duration. If any one of the impulse relays 2|, 22 and 23 releases before its associated test relay releases, a circuit is closed for operating relays 33 and 3|. Relay 3| closes a circuit for holding relays 30 and 3| operated independent of the test relays. Relay 30 closes a circuit for operating the alarm 32 and at its upper front contact short circuits the windings of impulse relays 2 22 and 23 thereby blocking further operation of these relays so as to retain in the impulse register 33 the record of the impulses already received.

What is claimed is:

1. An impulse testing device comprising an impulse receiving relay, a test relay, a condenser, a circuit including a contact of said impulse relay for charging said condenser, and a circuit rendered effective upon the opening of said contact for discharging said condenser through a winding of the test relay, the discharge current being effective to operate and hold the test relay operated for a desired length of time.

2. An impulse testing device comprising an impulse receiving relay, a test relay, a condenser, a circuit including a contact of said impulse relay for charging said condenser, and a circuit rendered effective upon the opening of said contact for discharging said condenser through a winding of the test relay, the discharge current being effective to operate and hold the test relay operated for a desired length of time, and an alarm circuit closed by said contact of the impulse relay and a contact of said test relay.

3. An impulse testing device comprising an impulse receiving relay, a test relay, a condenser, a circuit including contacts of both of said relays for charging said condenser, and a circuit rendered effective upon the opening of said contact of the impulse relay for discharging said conr denser through the operating winding of said test relay, the discharge current being effective to operate and hold the test relay operated for a desired length of time.

4. An impulse testing device comprising an impulse receiving relay, a test relay, a condenser, a circuit including contacts of both of said relays for charging said condenser, and a circuit rendered efiective upon the opening of said contact of the impulse relay for discharging said condenser through the operating Winding of said test relay, the discharge current being effective to operate and hold the test relay operated for a desired length of time, and an alarm circuit including said contact of the impulse relay and another contact of said test relay,

5. In a signaling system, a line, a signal sender for sending signal impulses over said line, and an impulse testing device comprising an impulse relay for responding to impulses transmitted over said line, a test relay, a condenser connected in series with the operating winding of said test relay, a circuit for charging said condenser, and a circuit rendered effective by the response of said impulse relay to an impulse in said signal circuit for discharging said condenser, said condenser having the capacity required for operating and holding said test relay operated for a definite interval of time.

6. In a signaling system, a line, a signal sender for sending signal impulses over said line, and an impulse testing device comprising an impulse relay for responding to impulses transmitted over said line, a polarized test relay having a biasing winding and an operating winding, a condenser connected in series with the operating winding of said test relay, a. circuit for charging said condenser, energization of the operating winding of the test relay by the charging current being effective to aid the biasing winding, and a circuit rendered effective by the response of said impulse relay to an impulse in said signal circuit for discharging said condenser, said condenser having the capacity required for operating and holding said test relay operated for a definite interval of time, which interval is the length of time that said impulse relay is operatively affected by an impulse of minimum allowable duration in said signal circuit.

'7. In a signaling system, a line, impulse receiving relays connected to said line, a first one of said relays being operatively responsive to current impulses of one polarity and a second one of said relays being operatively responsive to cur-- rent impulses of opposite polarity, test relays, one for each of said impulse relays, condensers, a circuit including a contact of said first impulse relay for charging a first one of said condensers, a circuit including a contact of said second impulse relay for charging a second one of said condensers, a circuit rendered effective by the operation of said first impulse relay for discharging said first condenser through a winding of the associated test relay to operate said test relay, a circuit rendered effective by the operation of said second impulse relay for discharging said condenser through a winding of the associated test relay to operate said test relay, an auxiliary relay, and circuits for operating said auxiliary relay, a first one of said last-mentioned circuits being closed by the release of said first impulse relay while the associated test relay is operated and a second one of said last-mentioned circuits being closed by the release of said second impulse relay While the associated test relay is operated.

8. In a signaling system, a line, impulse receiving relays connected to said line, a first one of said relays being operatively responsive to current impulses of not less than a certain magnitude, a second one of said relays being operatively non-responsive to current impulses of said certain magnitude and operatively responsive only to impulses of a higher magnitude, test relays, one for each of said impulse relays, condensers, a circuit including a contact of said first impulse relay for charging a first one of said condensers, a circuit including a contact of said second impulse relay for charging a second one of said condensers, a circuit rendered ef- 15 fective by the operation of said first impulse relay for discharging said first condenser through a Winding of the associated test relay to operate said test relay, a circuit rendered effective by the operation of said second impulse relay for dis-- impulse relay while the associated test relay is operated and a second one of said last-mentioned circuits being closed by the release of said sec:- ond impulse relay while the associated test relay is operated.

ROBERT O. SOFFEL. 

